排序方式： 共有97条查询结果，搜索用时 546 毫秒
61.
Banerjee RR Rangwala SM Shapiro JS Rich AS Rhoades B Qi Y Wang J Rajala MW Pocai A Scherer PE Steppan CM Ahima RS Obici S Rossetti L Lazar MA 《Science (New York, N.Y.)》2004,303(5661):1195-1198
The association between obesity and diabetes supports an endocrine role for the adipocyte in maintaining glucose homeostasis. Here we report that mice lacking the adipocyte hormone resistin exhibit low blood glucose levels after fasting, due to reduced hepatic glucose production. This is partly mediated by activation of adenosine monophosphate-activated protein kinase and decreased expression of gluconeogenic enzymes in the liver. The data thus support a physiological function for resistin in the maintenance of blood glucose during fasting. Remarkably, lack of resistin diminishes the increase in post-fast blood glucose normally associated with increased weight, suggesting a role for resistin in mediating hyperglycemia associated with obesity. 相似文献
62.
Rasmussen M Guo X Wang Y Lohmueller KE Rasmussen S Albrechtsen A Skotte L Lindgreen S Metspalu M Jombart T Kivisild T Zhai W Eriksson A Manica A Orlando L De La Vega FM Tridico S Metspalu E Nielsen K Ávila-Arcos MC Moreno-Mayar JV Muller C Dortch J Gilbert MT Lund O Wesolowska A Karmin M Weinert LA Wang B Li J Tai S Xiao F Hanihara T van Driem G Jha AR Ricaut FX de Knijff P Migliano AB Gallego Romero I Kristiansen K Lambert DM Brunak S Forster P Brinkmann B Nehlich O Bunce M Richards M Gupta R 《Science (New York, N.Y.)》2011,334(6052):94-98
We present an Aboriginal Australian genomic sequence obtained from a 100-year-old lock of hair donated by an Aboriginal man from southern Western Australia in the early 20th century. We detect no evidence of European admixture and estimate contamination levels to be below 0.5%. We show that Aboriginal Australians are descendants of an early human dispersal into eastern Asia, possibly 62,000 to 75,000 years ago. This dispersal is separate from the one that gave rise to modern Asians 25,000 to 38,000 years ago. We also find evidence of gene flow between populations of the two dispersal waves prior to the divergence of Native Americans from modern Asian ancestors. Our findings support the hypothesis that present-day Aboriginal Australians descend from the earliest humans to occupy Australia, likely representing one of the oldest continuous populations outside Africa. 相似文献
63.
Cerdeira M Martini S Hartel RW Herrera ML 《Journal of agricultural and food chemistry》2003,51(22):6550-6557
The effects of addition of the sucrose esters (SE) P-1670, P-170, and S-170 to a high-melting fraction of milk fat (HMF) and its blends with sunflower oil (SFO) on nucleation and growth were studied by laser polarized light turbidimetry and polarized light microscopy (PLM). The three SE delayed nucleation of HMF at the temperatures selected. P-1670 did not modify average crystal size after 3 h at crystallization temperature (T(c)) or crystal size distribution and modified crystallization kinetics only slightly. P-170 and S-170, however, markedly diminished crystal size and narrowed crystal size distribution. Activation free energies of nucleation at equivalent supercooling, calculated using the Fisher-Turnbull equation, significantly increased with addition of SE. According to these results, among the mechanisms described in the literature for fats or emulsions, the cocrystallization hypothesis is the one that better described the effects of sucrose esters on crystallization behavior in these systems. 相似文献
64.
Mônica Matoso Campanha Ricardo Henrique Silva Santos Gilberto Bernardo de Freitas Hermínia Emília Prieto Martinez Silvana Lages Ribeiro Garcia Fernando Luiz Finger 《Agroforestry Systems》2004,63(1):75-82
This research compared coffee plants (Coffea arabica L.) grown in an agroforestry and monoculture systems. Data were collected during two years, on vegetative growth, reproductive
development, nutritional status and yield of coffee, besides monitoring air temperature and the tree growth. All trees in
agroforestry system increased in growth, resulting in a reduction in the magnitude of the diurnal temperature variation and
also maximum temperature. Coffee plants in agroforestry system had less branch growth and leaf production, more persistent
and larger leaves, and presented earlier flowering, with a smaller number of productive nodes and flower buds, leading to
smaller berry yield than plants in monoculture system. In both systems, the coffee plants showed adequate leaf nutrient levels,
except for P and K. The yield of 2443 kg ha-1 of coffee from the monoculture was greater than 515 kg ha-1 of coffee from the agroforestry system. 相似文献
65.
High intensity ultrasound (HIU) was used to change the crystallization behavior, generate small crystals, and improve the texture of a low saturated shortening (interesterified soybean oil). Samples were crystallized at different temperatures (26, 28, 30, and 32 °C) without and with the application of HIU. Different acoustic power levels (110, 72, 61, 54, and 44 W) were used. Results show that higher acoustic powers had a greater effect on crystal size reduction, induced crystallization, and generated harder, more elastic and viscous materials. These effects were more significant when HIU was applied in the presence of crystals and when the sample was crystallized at 32 °C. 相似文献
66.
Claudina Vissio Silvana Andrea Dieser Héctor Luis Agnelli Liliana Mónica Odierno Alejandro José Larriestra 《Preventive veterinary medicine》2014
The somatic cell count (SCC) is considered an important indicator of intra-mammary infection (IMI). The purpose of this study was to determine the accuracy of both SCC and culture to detect IMI and their conditional dependence by means of latent class methods. This study involved 175 dairy cows from 2 herds with different udder infection prevalences. Quarter and composite milk samples were collected for SCC and bacteriological culture. Latent-class models using Bayesian methods were used to estimate test sensitivity (Se) and specificity (Sp) and population prevalence. The models ran involved only major mastitis pathogens and composite SCC (CSCC). Five thresholds between 100,000 and 300,000 cells/mL were evaluated and the receiver operating characteristics (ROC) curve analysis was performed. Fifty-five percent of the cows had CSCC ≥200,000 cells/mL and 95.4% of the cows had at least one infected quarter either with minor or major pathogens. Considering a threshold of 150,000 cells/mL, the estimated Se and Sp for the CSCC were, 0.80 (95% CrI 0.71–0.88) and 0.57 (95% CrI 0.44–0.71), respectively. The estimated culture Se and Sp were 0.83 (95% CrI 0.73–0.93) and 0.89 (95% CrI 0.74–0.98), respectively. There was no evidence of dependence between CSCC and culture. The area under curve for CSCC was 0.72. To the best of our knowledge, this is the first report of the CSCC accuracy to detect IMI for major pathogens considering the effect of culture misclassification. The estimates provided here could help to examine the performance of sampling schemes based on CSCC to manage udder health. 相似文献
67.
68.
This review presents the clinical, dermato-histopathological and genetic features of canine X-linked ectodermal dysplasia in previously reported cases and in three new spontaneous cases. The condition is compared with anhidrotic ectodermal dysplasia in humans and, based on current genetic concepts, we suggest that the two conditions are caused by the same gene and, consequently, represent a single pathological entity that affects both humans and dogs. 相似文献
69.
Bruno S. Vieira Joao G. Caramori Junior Gerusa S. S. Correa Ines G. Colvara Emanuele Brusamarelo Thuani V. S. Pereira Silvana A. P. V. Barbosa Cleber F. S. Oliveira 《Journal of animal physiology and animal nutrition》2019,103(2):555-563
An experiment was conducted to evaluate the effects of phytase (PHY), alone or in combination with citric acid (CA), on growing Japanese quails under moderate and severe phosphorus (P) restriction. For this, 504 one‐day‐old female quails were distributed in a completely randomised design with seven treatments and six replications. Treatments consisted of the following diets: (a) positive control (PC): formulated according to quails nutritional requirements; (b) negative control 40% (NC40): PC with 40% less aP; (c) NC40+PHY; (d) NC40+PHY+CA; (e) negative control 65% (NC65): PC with 65% less aP; (f) NC65+PHY; (g) NC65+PHY+CA. Phytase and CA were included at 300 FTU/kg and 40 g/kg, respectively. Performance, bone mineralization and plasma mineral concentration were evaluated at day 35; calcium (Ca) and P metabolism, between days 36 and 39. No significant differences in performance, plasma Ca and P were detected between quails fed PC or NC40; however, NC40 decreased tibia ash (p < 0.01). Treatment NC65 impaired daily weight gain (p = 0.01), tibia ash (p < 0.01), and tibia optical densitometry (p = 0.03), as well as modified plasma Ca (p < 0.01) and P (p = 0.03) concentrations when compared to PC. Both NC40 and NC65 reduced P excretion (p < 0.01). Phytase alone restored tibia ash of NC40 quails to regular rates. Nevertheless, only PHY and CA combined returned plasma P, tibia ash, tibia optical densitometry, and daily weight gain of quails fed NC65 to similar values as those observed in PC. In conclusion, PHY alone suppresses the negative effects of moderate P restriction in growing Japanese quails, but fails in this task under severe P restriction. In such a situation, only the combination of PHY and CA ensures regular rates of growth and bone mineralization. This concept should be better explored by producers in order to take full advantage of the reduction in P excretion achieved by lowering dietary P concentrations. 相似文献
70.
Daniella Aparecida de Jesus Paula Luis David Solis Murgas Tssia Flvia Dias Castro Isadora de Lima Assis Rafael Vilhena Reis Neto Silvana Marcussi 《Reproduction in domestic animals》2019,54(7):1034-1043
This study aims to investigate the effect of different cooling rates on the semen cryopreservation of curimba (Prochilodus lineatus). Nineteen ejaculates were obtained from adults males and cryopreserved at 15°C/min (CR15), 30°C/min (CR30) (controlled temperature inside and outside straw, speed was stable during freezing) and direct freezing in liquid nitrogen vapour (~35.6°C/min) (CRNV). The straws were thawed and seminal parameters evaluated. DNA fragmentation through the comet assay was assessed. A fresh sperm sample was not frozen and used for analyses. Data were submitted to an analysis of variance (ANOVA), and means were compared by Scott–Knott test (p < 0.05) using the R Software. Mean motility percentage was 100%, and motility duration was 39.5 ± 5.7 s for the fresh sperm (subjective analysis); 58.9 ± 8.0% and 24.5 ± 5.7 s for CR15; 64.8 ± 4.8% and 26.5 ± 7.1 s for CR30; and 50.1 ± 16% and 25.7 ± 4.7 s for CRNV, respectively. Motility percentages were higher and equal between CR15 and CR30 compared to CRNV (p < 0.05). Some sperm motion kinetics, namely average path velocity (VAP) and straight line velocity (VAS), were higher for CR30 (p < 0.05), while curvilinear velocity (VCL) and velocity progression (PRO) were lower for CRNV (p < 0.05). Straightness (STR) and wobble (WOB) were the same among treatments (p > 0.05). Sperm morphology results indicated higher means for total morphological sperm alterations in CRNV. All cooling rates caused sperm DNA fragmentation, although CR30 provided a less harmful effect. This is the first report for cryopreserved P. lineatus sperm preserved under different controlled cooling rates. The cooling rate of 30°C/min is indicated for the cryopreservation of this fish sperm as it led to the lowest detrimental spermatozoa effects. 相似文献